Impact of chlorpyrifos on cerebrum and cerebellum maturity in suckling rats

The purpose of our study is to assess the effect of chlorpyrifos (CPF) on rat cerebral and cerebellar maturity during the suckling period. Female Wistar rats were given 0.2?g?L^?1 of CPF in drinking water, equivalent to 40?mg?kg^?1 of body weight?day^?1, from day zero until day ten after delivery. In treated pups, plasma butyrylcholinesterase (BuChE) activity was inhibited by 70%. Cerebrum and cerebellum acetyl-cholinesterase (AchE) activities were reduced by 71 and 75%, respectively. The results suggest that CPF was distributed in pup tissues through the milk of lactating mothers, resulting in inhibition of AchE activities. At age 10 days, the CPF-treated pups showed a 28% decrease in body weight, a 23 and 41% decrease in plasma free T₃ and T₄ levels and reduction in cerebral and cerebellar protein content by 36 and 38%, respectively. Consistent histological changes were found in the cerebellum of CPF treated pups, with the external granular layer being markedly developed, the Purkinje cell bodies being poorly differentiated and abnormally distributed into the internal granular layer.     

Protective effects of curcumin on antioxidant status,body weight gain,and reproductive parameters in male rats exposed to subchronic 2,3,7,8-tetrachlorodibenzo-p-dioxin

The aim of this study was to investigate the effects of curcumin (CUR) on antioxidant status, body weight (BW) gains, and some reproductive parameters in male rats exposed to subchronic doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Thirty-two rats were divided into four groups. The first group was kept as control. The second group (TCDD group) was given TCDD at a dose of 50 ng·kg^?1 BW per day; the third group (CUR group) was treated with CUR at a dose of 80 mg·kg^?1 BW per day. The fourth group (TCDD + CUR group) was given TCDD and CUR at the same doses simultaneously. Malondialdehyde (MDA) levels were significantly increased in the TCDD group. In addition, TCDD exposure decreased liver superoxide dismutase (SOD) activity, catalase (CAT) activities of kidney and brain, glutathione peroxidase (GSH-Px) activities of liver, kidney, and brain, and glutathione levels of liver, kidney, and heart. However, CUR treatment with TCDD exposure decreased MDA levels in all tissues and increased SOD activities of liver, kidney, and brain, CAT activity of heart, and GSH-Px activities of heart and brain. TCDD caused a decrease in BW gain, and CUR partially eliminated this effect of TCDD. In addition, while reproductive organ weights, sperm concentration, and sperm motility tended to decrease with TCDD exposure, these effects tended to be close to normal levels by CUR treatment. In conclusion, CUR was seen to be effective in the treatment and prevention of toxicity induced by subchronic TCDD exposure.     

Effects of shear force on formation and properties of anoxic granular sludge in SBR

This paper reports the effects of shear force on anoxic granular sludge in sequencing batch reactors （SBR）. The study was carried out in two SBRs （SBR1 and SBR2） in which sodium acetate （200mg COD·L^-1） was used as the sole substrate and sodium nitrate （40 mgNO3-N·L^-1） was employed as the electron acceptor. The preliminary objective of this study was to cultivate anoxic granules in the SBR in order to investigate the effects of shear force on the formation of anoxic granular sludge and to compare the properties of anoxic sludge in the SBR. This study reports new results for the values of average velocity gradient, a measure of the applied shear force, which was varied in the two SBRs （3.79 s^-1 and 9.76 s^-1 for SBR1 and SBR2 respectively）. The important findings of this research highlight the dual effects of shear force on anoxic granules. A low shear force can produce large anoxic granules with high activity and poor settling ability, whereas higher shear forces produce smaller granules with better settling ability and lower activity. The results of this study show that the anoxic granulation is closely related to the strength of the shear force. For high shear force, this research demonstrated that： 1） granules with smaller diameters, high density and good settling ability were formed in the reactor, and 2） granular sludge formed faster than it did in the low shear force reactor （41days versus 76 days）. Once a steady-state has been achieved, the nitrate and COD removal rates were found to be 98% and 80%, respectively. For low shear force, such as was applied in SBR1, this research demonstrated that： 1） the activity of anoxic granular sludge in low shear force was higher than that in high shear force, 2） higher amount of soluble microbial products （SMPs） were produced, and 3） large pores were observed inside the larger granules,which are beneficial for nitrogen gas diffusion. Electron microscopic examination of the anoxic granules in both reactors showed that the morphology of the granules was ellipsoidal with a clear outline. Coccus and rod-shaped bacteria were wrapped by filamentous bacteria on the surface of granule.     

环境激素的内分泌干扰机制及其对人体的影响

环境激素问题的调查研究标志着地球环境时代的到来。重点讨论了环境激素的分类、特征及其内分泌干扰机制,并涉及了环境激素对人体的影响,以期引起人们的关注和重视,加强这方面的调查研究。     

3GY型粉体无尘装车机的开发与应用

应用自主知识产权,采用“密闭输送、最小落差、零匝输送、软连接和科学运行管理”技术,科学组合,研究开发成功粉体无尘装车机,科学消除了高温,高压、高料位条件下贮仓放料,常规除尘器出灰和粉体转输与装车的粉尘污染与资源流失。     

三峡库区复杂地形下的降雨时空分布特点分析

根据三峡水库坝区周边10个气象站1992~2002年逐日降雨资料,先用比值法将短期考察资料延长,再通过对比、回归等方法,客观分析降雨量、降雨日数、暴雨量、暴雨日数等指标随时间（年内、年际）和地形（高度、坡向）的变化,其特点如下：三峡坝区冬干、夏雨、秋雨明显,近年降雨增多;与武汉市相比,有降雨日多但降雨量、暴雨日及大暴雨日少的特点;降雨量、降雨日数、暴雨量、暴雨日数等多随高度上升而递增;由于受南北边山地阻挡和峡谷的影响,长江以南降雨大于长江以北;水体抑制库周降雨,且夜间比白天明显,强降雨过程比弱降雨过程明显。三峡地区降雨周边山地多于谷底,蓄水后差异将更明显,使地质灾害容易发生,应引起高度重视。     

Laboratory study on high-temperature adsorption of HCI by dry-injection of Ca（OH）2 in a dual-layer granular bed filter

Combustion-generated hydrogen chloride （HCl） is considered to be a very hazardous acid gaseous pollutant. This paper presents a laboratory study on the dry adsorption of HCl. The experiments were conducted in a dual-layer granular bed filter, at gas temperatures of 500℃-700℃ and n（Ca）/n（Cl）molar ratios of 1.0-5.0 using the silver nitrate titration method by dry adsorbent powders Ca（OH）2. Mainly, the adsorption efficiency of HCI and utilization efficiency of Calcium were studied, by varying relevant factors including n（Ca）/n（Cl）, tempera- ture, feeding method, water vapor and CO2. With a relatively higher HCl concentration of 1000ppm, the experimental results revealed that 600℃ may be the optimum temperature for HCl adsorption when optimum n （Ca）/n（Cl） was 2.5 in our tests. The results also demonstrated that the feeding at a constant pressure was more effective, and the HCl adsorption efficiency could rapidly reach over 90% with n（Ca）/n（Cl） = 2.5 at 600℃. Furthermore, the HCl adsorption efficiency was found to be slightly promoted by water vapor, while could be impeded by CO2, and the utilization efficiency of calcium could be up to 74.4% without CO2, while was only 36.8% with CO2 when n（Ca）/n（Cl） was 2.5 at 600℃.     

基于AHP-熵权法的石化企业承灾体脆弱性评估

针对石化企业化工事故引发的区域脆弱性研究不足现状,构建脆弱性评估模式。该模式以石化企业承灾体常见事故类型分析为基础构建脆弱性评估指标体系,集成层次分析法和熵权法确定权重并引入多变量Kendall协和系数检验一致性,在此基础上运用模糊综合评价法评估其脆弱性等级。将该模式应用于某石化企业,得到企业内不同区域的脆弱性等级分布。案例应用表明:AHP-熵权法应用于确定指标权重能更好的综合主客观因素的影响,评估结果可指导企业采取事故控制和灾害预防措施,更好的控制区域风险。     

UASB-SBR处理工艺试验研究

介绍了升流式厌氧污泥床反应器 (UASB) -序批式活性污泥法 (SBR)处理淀粉废水的工艺 ,详细叙述了该类废水的特点、试验系统组成、UASB的启动到污泥颗粒化的过程 ,以及处理效果。试验结果表明该处理系统具有耐冲击负荷 ,处理效果稳定 ,运行管理简单 ,运行成本低等特点。废水经颗粒化UASB稳定处理后 ,出水COD可降到 5 0 0mg/L以下 ,然后经SBR稳定处理后 ,出水COD可降到 10 0mg/L以下     

不同结构芳香酸对厌氧颗粒污泥特性与微生物群落的影响

以苯甲酸（BA）、邻苯二甲酸（PA）、连苯三甲酸（HA）、1-萘甲酸（1NA）为研究对象,探究了不同结构芳香酸对厌氧颗粒污泥理化特性与微生物群落的影响.结果表明,在40 d的接触实验中,1NA实验组对溶解性化学需氧量（SCOD）的去除率为86.09%,与空白对照组相比降低了7%.4个实验组污泥疏松胞外聚合物（LB-EPS）和紧密胞外聚合物（TB-EPS）中多糖含量分别比对照组高0.30~1.28、0.19~1.03 mg·g^-1,蛋白含量分别提高了0.025~0.326、0.007~0.171 mg·g^-1.在LB-EPS三维荧光（EEM）光谱中,HA和1NA实验组中出现了类腐殖酸物质荧光峰,且辅酶F₄₂₀峰强度有所降低.对于酶活性而言,HA、1NA实验组乙酸激酶相对活性比对照组减少了65.26%、6.93%.通过高通量测序发现,对照组与实验组中的优势菌群均为Proteobacteria、Chloroflexi和Firmicutes.HA与1NA的加入降低了Actinobacteria的相对丰度,提高了Bacteroidetes和Synergistetes的相对丰度.对于古细菌而言,Methanothrix在对照组与实验组中为优势种属,其相对丰度达到49.95%~80.40%;但实验组Methanothrix的相对丰度减少了10.69%~30.45%,且1NA实验组尤为明显;而1NA的加入提高了Methanospirillum的相对丰度,达到34.08%.同时,细菌和古细菌代谢通路预测表明,其主要功能组为代谢、遗传信息处理、环境信息处理和细胞过程,芳香酸使得厌氧颗粒污泥中氨基酸的代谢功能有所增强.